Field of the Invention
This invention relates generally to inflator devices such as used in motor vehicle occupant safety restraint systems and, more particularly, to inflator devices having or formed to contain an integral clamp stop.
Discussion of Related Art
It is well known to protect a vehicle occupant by means of safety restraint systems which self-actuate from an undeployed or static state to a deployed state without the need for intervention by the operator, i.e., “passive restraint systems.” Such systems commonly contain or include an inflatable vehicle occupant restraint or element, such as in the form of a cushion or bag, commonly referred to as an “airbag cushion.” In practice, such airbag cushions are typically designed to inflate or expand with gas when the vehicle encounters a sudden deceleration, such as in the event of a collision.
Such airbag cushions may desirably deploy into one or more locations within the vehicle between the occupant and certain parts of the vehicle interior, such as the doors, steering wheel, instrument panel or the like, to prevent or avoid the occupant from forcibly striking such parts of the vehicle interior. For example, typical or customary vehicular airbag cushion installation locations have included in the steering wheel, in the dashboard on the passenger side of a car, along the roof line of a vehicle such as above a vehicle door, and in the vehicle seat such as in the case of a seat-mounted airbag cushion. Other airbag cushions such as in the form of knee bolsters and overhead airbags also operate to protect other or particular various parts of the body from collision.
In addition to one or more airbag cushions, inflatable passive restraint system installations also typically include a gas generator, also commonly referred to as an “inflator.” Upon actuation, such an inflator device desirably serves to provide an inflation fluid, typically in the form of a gas, used to inflate an associated airbag cushion.
Various types or forms of such passive restraint assemblies have been developed or tailored to provide desired vehicle occupant protection based on either or both the position or placement of the occupant within the vehicle and the direction or nature of the vehicle collision. Automotive passenger side airbag installations generally incorporate an airbag module assembly having an inflator device within a module housing or canister and an inflatable airbag cushion adapted to inflate out a side of the module housing. In one currently used passenger side airbag module assembly configuration the inflatable airbag cushion is adapted to inflate out a top side of the module canister, often referred to as a “top mounted” airbag cushion. Such a module assembly is installed in the dashboard of the automobile close to the windshield. Upon activation, the inflator device releases inflation gas which inflates the airbag cushion. The top mounted airbag cushion initially inflates toward the windshield and then rapidly rolls down the dashboard in a direction toward the passenger.
Various types or forms of inflator devices have been disclosed in the art for use in inflating an inflatable restraint system airbag cushion. One such inflator device, generally known as a hybrid airbag inflator, uses high temperature reaction products, typically also including additional gas products, generated by the reaction of a reactive material, to increase the gas pressure within the inflator, rupturing a rupturable seal and inflating one or more airbag cushions. In some cases, the stored and pressurized gas may include or form an oxidizing gas to assist in more fully converting the reaction products generated by the reaction of the reactive material, to compounds such as carbon dioxide and water.
Hybrid inflators are commonly composed of a tubular hybrid inflator housing containing a supply of reactive material and a supply of pressurized gas supplying material. In practice, such tubular inflator housing have an elongated tubular form and are connected or secured in an associated module housing via one or more retainer devices or features. For example, commonly-assigned U.S. Pat. No. 5,405,164 to Paxton et al. discloses hybrid inflator retention in an automotive airbag module using a diffuser sheet fastened to a reaction canister that encloses the hybrid inflator. Commonly assigned U.S. Patent Application Publication 2010/0181746 to Rose et al. discloses the use of a retainer clamp in securing a tubular inflator within an airbag module housing. Commonly assigned U.S. Pat. No. 8,505,963 to Lewis et al. discloses airbag module assemblies having a strap and clamp system to securely hold an inflator relative to a housing.
The size, shape, and components of airbag inflators can vary depending on the vehicle and where in the vehicle the airbag inflator is used, e.g., driver side or passenger side. In addition, the size of the reactive material load contained within such an inflator structure is generally predetermined in order to be sufficient to result in desired inflation of the associated airbag cushion upon actuation of the inflator. As will be appreciated, the incorporation and use of a different sized inflator are often necessary to change or alter the inflation performance provided by the inflator system.
At least in part as a consequence of the significant design changes that may be required to permit the incorporation and use of inflator devices between applications requiring or desiring different inflation performances, module assemblies that utilize attachment or retention clamps for retention of tubular inflator housings within modules have been proposed. Unfortunately, the use of relatively costly high-clamp-force retention clamps and/or multiple retention clamps are typically required to effect required module inflator retention. Moreover, in view of the high levels of pressure and stress exerted on or in such a module assembly upon or during inflator actuation and airbag deployment, there is a need and a demand for improved means and techniques for securing an inflator housing within an associated module housing such as to minimize and preferably avoid undesired movement of the inflator device within the associated module while not unnecessarily complicating production and assembly.